let  arr = [53, 27, 36, 15, 69, 42 ];
InserSort(arr);
console.log(InserSort(arr))
function InserSort (arr) {
  let length  =  arr.length;
  if (length<0) {
      return
  }
  for (let index = 0; index < length; index++) {
      let current = arr[index];
      let preIndex  = index - 1;
      while(preIndex>=0&&current < arr[preIndex]) {
          arr[preIndex+1] = arr[preIndex]
          preIndex --
      }
      arr[preIndex+1] = current
  }
  return arr
}